As technology has improved, various types of sensors and control devices have been placed in hydrocarbon wells, including subsea wells. Examples of sensors include pressure sensors, temperature sensors, and other types of sensors. Additionally, sensors and control devices on the sea floor, such as sand detectors, production sensors and corrosion monitors are also used to gather data. Information measured by such sensors are communicated to well surface equipment over communications links. Control devices can also be controlled from well surface equipment over a communications link. Examples of control devices include flow control devices, pumps, choke valves, and so forth.
Certain solutions exist to communicate control and data information between subsea wellhead equipment and a surface facility (such as a sea vessel or a land-based facility). Conventionally, the communications link between the subsea wellhead equipment and the surface facility is implemented with electrical wires run in an umbilical from the subsea wellhead equipment to the surface facility.
Communications of data and control information over such electrical wires are usually defined by proprietary protocols that differ by well operator. A shortcoming of modems that communicate using such conventional proprietary protocols is that the communication bandwidth can be rather limited. For example, in one conventional wire-based subsea communications link defined according to a proprietary protocol, the data rate over the communications link is 9600 bits per second.
As sensors and control devices have become more complex and the number of such devices has increased in subsea wells, the amount of data that is transferred over the umbilical communications link between the subsea wellhead equipment and the surface facility can be quite large. Conventional umbilical communications links do not offer the bandwidth that allows for the transfer of large amounts of data over the links. Therefore, the types and number of sensors and/or control devices that can be used in subsea applications or the communication rate of sensor data or control commands may be limited.